1. Technical Field
Embodiments of the subject matter disclosed herein generally relate to methods and devices used for estimating a location of a target device moving through water and carrying a receiver that detects waves emitted by a source at a known location, and, more particularly, to using interval analysis based on the phase of the detected wave to estimate the location of the target device.
2. Discussion of the Background
Autonomous underwater vehicles (AUVs) are unmanned underwater vehicles (i.e., robots) often used in the oil and gas industry, for example, to perform tasks related to equipment used in marine seismic surveys. For example, AUVs may be used to remove marine growth that becomes attached to birds mounted on streamers. The AUV's may also be used for collecting seismic data.
Since they are moving underwater, AUVs positions cannot be determined based on Global Positioning System signals. Therefore, an AUV navigates using an underwater acoustic positioning system based on detecting waves generated by sources at known positions. If the waves are generated at more than one known position, the AUV's position may be determined by triangulation. However, during marine seismic surveys, waves may be generated from a single location (e.g., a source attached to the vessel towing the streamer). In these circumstances, effectively determining a moving AUV's location becomes more difficult (imprecise or time-consuming), impinging on the AUV's operability.
Accordingly, it would be desirable to provide devices and methods for quickly and effectively determining the position of an underwater AUV, i.e., fast enough and with a precision that would not impede its operation.